809923 has 4 divisors (see below), whose sum is σ = 812440. Its totient is φ = 807408.

The previous prime is 809917. The next prime is 809929. The reversal of 809923 is 329908.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (809917) and next prime (809929).

It is a cyclic number.

It is not a de Polignac number, because 809923 - 2⁵ = 809891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (809929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 690 + ... + 1447.

It is an arithmetic number, because the mean of its divisors is an integer number (203110).

2⁸⁰⁹⁹²³ is an apocalyptic number.

809923 is a deficient number, since it is larger than the sum of its proper divisors (2517).

809923 is a wasteful number, since it uses less digits than its factorization.

809923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2516.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 809923 is about 899.9572212055. The cubic root of 809923 is about 93.2140212961.

The spelling of 809923 in words is "eight hundred nine thousand, nine hundred twenty-three".